Question About Weak Self Usage

Hello everyone. I have a small question about Weak Self. In the example below, I am doing a long process to the data I query with SwiftData. (For this reason, I do it in the background.) I don't know if there is a possibility of a memory leak when the view is closed because this process takes a long time.

import SwiftUI
import SwiftData

struct ActiveRegView: View {
    @Query(filter: #Predicate<Registration> {
        $0.activeRegistration
    }, animation: .default) private var regs: [Registration]


    @Environment(ViewModel.self) private var vm
    @State private var totalParkingFee: Decimal = 0
    
    var body: some View {
        ...
 .onAppear {
                    var totalParkingFee = Decimal()
                    DispatchQueue.global(qos: .userInitiated).async  {
                        for reg in regs {
                            totalParkingFee += vm.parkingFee(from: reg.entryRegistration.entryDate, to: .now, category: reg.category, isCustomPrice: reg.isCustomPrice)
                        }
                        
                        DispatchQueue.main.async {
                            withAnimation {
                                totalParkingFee = totalParkingFee
                            }
                        }
                        
                    }
                }
    }
   
}

I use ViewModel with @Environment, so I don't initilize ViewModel every time view is initilized. I know it's a simple question and I thank you in advance for your answers.